Hiya,
It will not do much good to call Faults as we have no choice in the bitrate used to transmit E4, This will be agreed by E4 and ntl at a set level and will be adheared to.
However if you do feel that this does require checking into then feel free to contact one of the mods/admin who can then forward your account details onto me and I'll look into it for you. Russ knows that I work for ntl, the others I cannot speak for , though I'm sure that they are aware I am Mark J (CLT) from the .com.